ORAU TEAM

Dose Reconstruction

Project for NIOSH

Oak Ridge Associated Universities I Dade Moeller & Associates I MJW Corporation

Page 1 of 25

Document Title:

Portsmouth Gaseous Diffusion Plant –

Occupational Medical Dose

Document Number: ORAUT-TKBS-0015-3

Revision: 02

Effective Date: 07/07/2006

Type of Document: TBD

Supersedes: Revision 01

Subject Expert: Paul J. Demopoulos

Document Owner

Approval: Signature on File Approval Date: 06/05/2006

Paul J. Demopoulos, TBD Team Leader

Approval: Signature on File Approval Date: 06/05/2006

John M. Byrne, Task 3 Manager

Concurrence: Signature on File Concurrence Date: 06/07/2006

Edward F. Maher, Task 5 Manager

Concurrence: Signature on File Concurrence Date: 06/06/2006

Kate Kimpan, Project Director

Approval: Signature on File Approval Date: 07/07/2006

James W. Neton, Associate Director for Science

 New Total Rewrite Revision Page Change

FOR DOCUMENTS MARKED AS A TOTAL REWRITE, REVISION, OR PAGE CHANGE, REPLACE THE PRIOR 

REVISION AND DISCARD / DESTROY ALL COPIES OF THE PRIOR REVISION
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date: 07/07/2006 Page 2 of 25

PUBLICATION RECORD

EFFECTIVE 

DATE

REVISION 

NUMBER DESCRIPTION

01/05/2004 00 New technical basis document for the Portsmouth Gaseous 

Diffusion Plant – Occupational Medical Dose. First 

approved issue. Initiated by Mark Notich.

07/19/2004 01 Incorporates comments from internal and NIOSH formal 

reviews. Approved Issue of Revision 01. Initiated by Mark 

Notich.

07/07/2006 02 Deletes the uterus as an analogue/surrogate organ in 

Table 3-10 on page 16 in Section 3.4.5 as per Task 5 

comment. Updates required introductory language on 

pages 6 and 7 in Section 3.1. Revised to change from a 

page change (Rev 01 PC-1-B) to a revision (Rev 02-A) as 

a result of NIOSH comment. Added a Purpose and Scope 

subsection to the Introduction (Section 3.1). Approved 

issue of Revision 02. This revision results in a reduction in 

assigned dose and no PER is required. Training required: 

As determined by the Task Manager. Initiated by Paul J. 

Demopoulos. 
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date: 07/07/2006 Page 3 of 25

TABLE OF CONTENTS

SECTION TITLE

Acronyms and Abbreviations ...............................................................................................................

PAGE

5

3.1 Introduction and Occupational Medical Dose ........................................................................... 6

3.1.1 Purpose......................................................................................................................... 7

3.1.2 Scope............................................................................................................................ 7

3.2 Examination Frequencies.........................................................................................................7

3.3 Equipment and Techniques......................................................................................................8

3.3.1 Photofluorography ......................................................................................................... 8

3.3.2 Pre-1970 ....................................................................................................................... 9

3.3.3 Type I (1970-1978)........................................................................................................ 9

3.3.4 Type II - III..................................................................................................................... 9

3.3.5 Diagnostic X-Ray Technique Generalizations 1954 to Date ........................................ 12

 3.3.5.1 Collimation..................................................................................................... 12

3.4 Organ Dose Calculations ....................................................................................................... 13

3.4.1 Photofluorography (1954-1957)................................................................................... 13

3.4.2 Pre-1970 (1958-1969) ................................................................................................. 14

3.4.3 Type I Machine (1970-1978) ....................................................................................... 14

3.4.4 Type II Machine (1979-1991)....................................................................................... 15

3.4.5 Type III Machine (1992-Present) ................................................................................. 15

3.5 Uncertainty.............................................................................................................................16

3.6 Dose Reconstructor Instructions ............................................................................................ 17

3.6.1 Assignment of Organ Doses from X-ray Procedures: 

 Approach for Dose Reconstructions............................................................................ 18

References ........................................................................................................................................19

ATTACHMENT A, OCCUPATIONAL MEDICAL DOSE ..................................................................... 21
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LIST OF TABLES

TABLE TITLE PAGE

3-1 Frequency of occupational chest X-rays at the PORTS............................................................ 7

3-2 Description of the X-ray equipment used at PORTS................................................................. 9

3-3 Technique factors used for each type of X-ray equipment...................................................... 10

3-4 Medical x-ray quality assurance parameters/PORTS ............................................................. 10

3-5 Half value layer limits ............................................................................................................. 11

3-6 Entrance skin exposure limits................................................................................................. 11

3-7 Relationship of beam intensity and various technical factors.................................................. 12

3-8 Default dose values by procedure.......................................................................................... 14

3-9 Default dose values by procedure.......................................................................................... 15

3-10 Analogues for IREP organs not included in ICRP 34.............................................................. 16

A-1 Dose equivalents for organs identified in ICRP 34 (1982) for P/A views................................. 22

A-2 Dose equivalent for IREP organs not included in ICRP 34 (1982) for P/A views .................... 23

A-3 Dose equivalents for organs identified in ICRP 34 (1982) beam quality for LAT views ........... 24

A-4 Dose equivalent for IREP organs not included in ICRP 34 (1982) for LAT views.................... 25
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ACRONYMS AND ABBREVIATIONS

A/P Anterior Posterior (x-ray view)

AAPM American Association of Physicists in Medicine

Al Aluminum (x-ray machine filtration)

DEP Ohio State Department of Environmental Protection

DOE U.S. Department of Energy

ESE Entrance Skin Exposure

ESEG Entrance Skin Exposure Guideline

FDA/BRH Food and Drug Administration Bureau of Radiological Health

GAT Goodyear Atomic Corporation Technical Report

HVL Half Value Layer

ICRP International Commission of Radiation Protection

IREP Interagency Radiation Exposure Program

kVp Kilovolts Peak or peak kilovoltage

LAT Lateral (x-ray view)

mA Milliampere

mAs Milliampere seconds

mR MilliRoentgen 

NCRP National Council on Radiation Protection and Measurements

NIOSH National Institute for Occupational Safety and Health

P/A Posterior Anterior (x-ray view)

PORTS Portsmouth Gaseous Diffusion Plant

QA Quality Assurance

RMS root mean square

SID Source to Image Distance

SSD Source to Skin Distance

TBD Technical Basis Document
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3.1 INTRODUCTION AND OCCUPATIONAL MEDICAL DOSE

The Portsmouth Gaseous Diffusion Plant (PORTS) required pre-employment physical examinations 

as part of their occupational health and safety program. These medical examinations typically 

included diagnostic chest x-rays. Medical x-rays during employment are offered every three years 

since 1989 but are not mandatory. The doses from these diagnostic x-ray procedures depended not 

only on the characteristics of the x-ray machine and the procedure used, but also on the frequency of 

the examination. Other types of x-rays such as lumbar, knee or ankle x-rays were given for on the job 

injuries at the discretion of the medical director but are not included in doses under EEOICPA. 

Technical basis documents and site profile documents are not official determinations made by the 

National Institute for Occupational Safety and Health (NIOSH) but are rather general working 

documents that provide historic background information and guidance to assist in the preparation of 

dose reconstructions at particular sites or categories of sites. They will be revised in the event 

additional relevant information is obtained about the affected site(s). These documents may be used 

to assist NIOSH staff in the completion of the individual work required for each dose reconstruction.

In this document the word “facility” is used as a general term for an area, building, or group of 

buildings that served a specific purpose at a site. It does not necessarily connote an “atomic weapons 

employer facility” or a “Department of Energy [DOE] facility” as defined in the Energy Employees 

Occupational Illness Compensation Program Act [EEOICPA; 42 U.S.C. § 7384l(5) and (12)]. 

EEOICPA defines a DOE facility as “any building, structure, or premise, including the grounds upon 

which such building, structure, or premise is located...in which operations are, or have been, 

conducted by, or on behalf of, the Department of Energy (except for buildings, structures, premises, 

grounds, or operations...pertaining to the Naval Nuclear Propulsion Program)” [42 U.S.C. § 

7384l(12)]. Accordingly, except for the exclusion for the Naval Nuclear Propulsion Program noted 

above, any facility that performs or performed DOE operations of any nature whatsoever is a DOE 

facility encompassed by EEOICPA.

For employees of DOE or its contractors with cancer, the DOE facility definition only determines 

eligibility for a dose reconstruction, which is a prerequisite to a compensation decision (except for 

members of the Special Exposure Cohort). The compensation decision for cancer claimants is based 

on a section of the statute entitled “Exposure in the Performance of Duty.” That provision [42 U.S.C. § 

7384n(b)] says that an individual with cancer “shall be determined to have sustained that cancer in the 

performance of duty for purposes of the compensation program if, and only if, the cancer...was at 

least as likely as not related to employment at the facility [where the employee worked], as 

determined in accordance with the POC [probability of causation1

As noted above, the statute includes a definition of a DOE facility that excludes “buildings, structures, 

premises, grounds, or operations covered by Executive Order No. 12344, dated February 1, 1982 (42 

U.S.C. 7158 note), pertaining to the Naval Nuclear Propulsion Program” [42 U.S.C. § 7384l(12)]. 

While this definition contains an exclusion with respect to the Naval Nuclear Propulsion Program, the 

section of EEOICPA that deals with the compensation decision for covered employees with cancer 

[i.e., 42 U.S.C. § 7384n(b), entitled “Exposure in the Performance of Duty”] does not contain such an 

exclusion. Therefore, the statute requires NIOSH to include all occupationally derived radiation 

exposures at the facility in its dose reconstructions for employees at DOE facilities, including radiation 

] guidelines established under 

subsection (c)...” [42 U.S.C. § 7384n(b)]. Neither the statute nor the probability of causation 

guidelines (nor the dose reconstruction regulation) define “performance of duty” for DOE employees 

with a covered cancer or restrict the “duty” to nuclear weapons work.

 

1 The U.S. Department of Labor is ultimately responsible under the EEOICPA for determining the POC. 
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exposures related to the Naval Nuclear Propulsion Program. As a result, all internal and external 

dosimetry monitoring results are considered valid for use in dose reconstruction. No efforts are made 

to determine the eligibility of any fraction of total measured exposure for inclusion in dose 

reconstruction. NIOSH, however, does not consider the following exposures to be occupationally 

derived:

• Radiation from naturally occurring radon present in conventional structures. 

• Radiation from diagnostic X-rays received in the treatment of work-related injuries. 

3.1.1

The purpose of this TBD is to describe the occupational X-ray program for the PORTS plant. This 

document discusses historical and current practices in relation to the evaluation of X-ray external 

exposure data for PORTS workers.

Purpose

3.1.2

This TBD contains supporting documentation to assist in the evaluation of occupational external X-ray 

doses from medical evaluations of workers at PORTS. An objective of this document is to provide 

supporting technical medical X-ray equipment data or survey information to evaluate, with claimant 

favorable assumptions for workers evaluated for work related reasons. 

Scope

3.2 EXAMINATION FREQUENCIES

X-ray examinations were conducted consistently for employees every three years from 1989 to

present. Included in the medical procedures is the frequency of chest x-rays that were offered based 

upon worker age. Note asbestos and beryllium workers were required to have annual x-rays. After 

the pre-employment physical examination, chest x-rays were optional. This information may be 

recorded in the worker file provided by the U.S. Department of Energy (DOE). All occupational x-rays 

in the worker file are to be included in the reconstruction of occupational dose.

Table 3-1 lists the frequencies of chest x-rays for different age groups through the years and also 

identifies specific groups of workers. Declared pregnant women were not x-rayed from at least 1989. 

Typically one Posterior/Anterior (P/A) view was taken but Anterior/Posterior (A/P) and Lateral (LAT) 

view(s) were possible. 

Table 3-1. Frequency of occupational chest X-rays at the PORTS. 

Period Frequency Comment

1954–1989a Annually All employees.

Annually Asbestos/beryllium workers.

1990–2003 Offered every 10 years Employees up to 30 years old.

Offered every 5 years Employees up to and equal to 45 years old.

Offered every 3 years Employees greater than 45 years old.

Annually Asbestos/beryllium workers.

PORTS medical records include notations in individual worker files regarding both the date and the 

purpose of the of x-ray examinations. Included in some of the more recent records is the number of 

views. The current Medical X-ray technician stated the number of re-takes was virtually none. This is 

because the employees had shown concern about how many x-rays they were given, (1993 – 

present). The complex-wide x-ray guidance Technical Basis Document (TBD) indicate a 3 % re-take 

rate based upon Trout et al (1973) in their analysis of the rejection rate of chest radiographs obtained 
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during the Coal Mine “Black Lung” program reported an average rejection rate of 3% among 67,000 

radiographs. International Commission of Radiation Protection (ICRP) Publication-34 (ICRP-34) 

indicates a minimal value of 10 –12 % re-takes (ICRP 34, p 37). A 5 % re-take value will be used to 

be claimant favorable. 

Retakes should serve as a signal to give special consideration to the evaluation of technique factors, 

and hence the resultant dose calculations. A retake in a very large individual might serve as a signal 

that the initial radiograph was taken with technique factor settings suitable for a smaller person, and 

that the second radiograph reflected an additional and larger dose. 

About 80 % of the x-rays given were P/A chest x-rays. The others comprised of knee, hand, ankle 

legs and others mostly for injuries sustained at work. 

Specific organ doses to be attributed for P/A chest x-rays calculated on the basis of the dose 

conversion factors found in ICRP Publication 34 are given in Attachment A, Table A-1and A-2. LAT 

dose conversion factors are given in Attachment A, Table A-3 and A-4. For organs not listed in ICRP 

Publication 34 but specified in the Interagency Radiation Exposure Program (IREP) code, doses were 

determined by analogy with anatomical location (Table 3-9). Thus IREP code organs in the thoracic 

cavity, but not mentioned in the ICRP Publication 34 were assigned the same dose as the lungs; 

doses to the organs in the head and neck were assigned the same dose as the thyroid. The head and 

neck organ dose estimates (i.e. eye/brain), should be somewhat greater than doses actually incurred 

(hence claimant favorable), because of geometry considerations and at least in the case of the brain, 

because of attenuation by the bony cranium. To ensure claimant favorability in the view of the 

variations in organ dose described in ICRP Publication 34 (p. 51), the doses for females (lungs), 

which are slightly higher than those for males, were used. 

3.3 EQUIPMENT AND TECHNIQUES

3.3.1

Chest photofluorography, which resulted in very much greater patient doses from a diagnostic 

procedure, was used sporadically until as late as the early 1960’s. Photofluorography used a smaller 

film (4 x 5 inches), a smaller source to skin distance (SSD) (42 inches), and both a higher peak 

kilovoltage (kVp) and typically a several fold greater exposure in terms of milliampere seconds (mAs). 

Exposure was regulated by photometers, which utilized the exposure to the film to determine the time 

of exposure. 

Photofluorography

Even-though no evidence of the use of photofluorography was found at PORTS it is reasonable to 

presume that at least some of the occupational medical diagnostic chest x-rays with the DOE and its 

predecessor organizations were accomplished by photofluorography. The use of photofluorography 

should be assumed to ensure claimant favorable dose reconstructions from the time-period of 1954 

through 1960. 

Photofluorography differed from conventional radiography with film in that while kVp and milliampere 

(mA) settings could be manipulated by the technician, the exposure time was regulated by the amount 

of light generated in the photofluorographic unit, with a cutoff or maximum exposure time. An 

exposure of 15 mAs (150 mA for 0.1 second) was sufficient to produce a satisfactory image on 35 mm 

film (four by five inches); larger film required greater exposures (Sante 1954, p. 129). 

Typical operating parameters reported for 1950’s photofluorography were 24 mAs at 83 kVp at a 

target to film distance of 36 inches (Braestrup 1958, p. 143), and 30 mAs at 90 kVp with a target to 
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film distance of 40 inches and 2.4 mm added filtration. In the absence of data, a HVL of 2.5 mm 

should be assumed for dose determinations and is claimant favorable. Measurements at the Hanford 

site indicated that for a 60 mAs photofluorography exposure at 100 kVp, the entrance skin exposure 

(ESE) was 1.53 R (Rising and Soldat 1959), which is likely an upper limit value based on a large 

patient and is consistent with an ESE of about 600-700 milliroentgen (mR) for a 24-30 mAs exposure 

at somewhat lower kVp. The Hanford measured value of 1.53R ESE is likely an upper limit and 

hence an overstatement of the actual exposure from photofluorography to the average patient, and 

thus this 1.53R ESE value should be used in the absence of data to ensure claimant favorability. 

3.3.2

The x-ray machine information prior to 1970 is not available. The ESE was based upon the complexwide x-ray TBD guidance as presented in Table 3-8. Default Dose Values by Procedure presented in 

section 3.3-1. An air kerma of 200 mR for P/A and 500 mR for Lat x-rays was utilized in the organ 

dose calculations.

Pre-1970

3.3.3

The x-ray machine information from 1970 - 1978 is not available. The ESE was based upon the 

complex-wide x-ray TBD guidance as presented in Table 3-8. Default Dose Values by Procedure 

presented in section 3.3.1. An air kerma of 100 mR for P/A and 250 mR for Lat x-rays was utilized in 

the organ dose calculations.

Type I (1970-1978)

3.3.4

The imaging system and generator have been the only changes since 1979. Currently in use is a GE 

MVP Micro x-ray 60 with a model COLL-C-150 x-ray tube. It can operate up to 150 kVp in a singlephase mode and up to 320 mA. ESE measurements do exist in some cases from the Ohio State 

Department of Environmental Protection (DEP), the Federal Drug Administration Bureau of 

Radiological Health (FDA/BRH) currently the Center for Devices and Radiological Health, and the 

Health Physics group at PORTS. However it is more claimant favorable to utilize the ESE values as 

calculated from the technique factors. 

Type II - III

Records concerning the medical x-ray equipment at PORTS from 1954 to 1979 were not located. A 

conversation with a physician that worked at the PORTS medical center within this time frame 

indicated that the employees went to three area hospitals for x-rays including the Southern Ohio 

Medical center during this time period for annual chest x-rays (Dr. Spears, conversation 9/18/03). 

A summary description of the x-ray equipment used at PORTS is included in Table 3-2. A summary 

of the specific technique factors for these machines is presented in Table 3-3. 

Table 3-2. Description of the X-ray equipment used at PORTS.

Technique Period Equipment

Photofluorography (PF) 1954-1960 No information available.

Pre-1970 1961-1969 No information available.

Type I 1970–1978 No information available. 

Type II 1979-1991 Hi-Speed Rare Earth Screens, Kodak X DMAT Model M-7B film Processor, 

GE MVP Micro x-ray 60 x-ray generator , GE Col C-150 x-ray Tube, 

Stationary 12:1 Grid, Film Processor, Manual timer, Manual techniques

Type III 1992–present Hi-Speed Rare Earth Screens, Kodak X DMAT Model M-7B film Processor, 

GE MVP Micro x-ray 60 x-ray generator , GE Col C-150 x-ray Tube (same as 

type II above), Stationary 12:1 Grid, Film Processor, Automatic timer, 

Phototimed exposures
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Table 3-3. Technique factors used for each type of X-ray 

equipment. 

Machine View

Current

(mA)

Voltage

(kVp)

Exposure time

(sec.)

Type I Techniques unknown. No records were kept with regard 

to the technique factors used during this time period. 

Type IIb P/Aa 200 110 1/10

Type IIIb P/A 200 110 1/10

a. P/A indicates a P/A view, the average P/A chest measures 26 cm. The 

average Lat. chest measures 34 cm. 

b. Manual technique factors obtained from PORTS medical x-ray 

technologist.

Since no technique factors were identified by PORTS for Type I equipment, organ doses based on 

assumed technique factors were developed on the basis of x-ray techniques contemporary with the 

time period (i.e. 1970-1978) with due consideration given to claimant favorability. Accordingly, it was 

assumed that the operating kVp was 80, somewhat higher (and hence claimant favorable) than the 

kVp values typically used at the time (Morgan and Carrigan, 1955; Laughlin et. al. 1957). To offset 

this lower kVp, an increased exposure would be required as compared with Type II exposures, and 

this was conservatively taken to be 30 mAs, based on exposure time of 0.1 second at 300 mA. 

External filtration was assumed to be 1.5 mm Aluminum (Al) as compared with 2.5 mm Al used 

subsequent to 1979, which would further increase the dose. The SSD was assumed to be 152cm 

based on a Source to Image Distance (SID) of 183cm less a chest thickness of 26cm and an addition 

of 5cm to account for cassette thickness. {The Hanford TBD indicates a 79 mR ESE or 4 mR/mAs 

value for earlier era x-rays.} (ORAUT-TKBS-0003 TBD, 2003 and ORAUT-TKBS-0006-3 TBD 2003)

Some measurement results follow. As can be seen it would be more claimant favorable to utilize 

technique factor information for all x-ray machines. One result for ESE (PORTS HP department 

measurement) at a SID of 178 cm, 124 kVp, 250 mA, 0.013 sec yielded 6.0 mR exposure or 1.84 

mR/mAs. (PORTS HP x-ray Quality Assurance (QA) survey, 1994) A second result for ESE (FDA 

8/24/92 measurement) at a SID of 178 cm, 23 cm chest LucAl phantom, 120 kVp, 200 mA, and 0.1 

sec yielded a 12.8 mR exposure or a 0.64 mR/mAs. A third result for ESE (FDA 8/24/92) at a SID of 

178 cm, 23 cm chest LucAl phantom at 110 kVp, 320 mA, 0.083 sec yielded a 16.7 mR exposure or 

0.62mR/mAs.

The x-ray equipment currently in use has been QA checked for entrance skin exposure (ESE) by the 

manufacturer since 1979 and from the Health Physics group since 1985. Although all of the records 

for these QA checks on the x-ray equipment could not be found, the records available indicate that the 

x-ray equipment was working within FDA guidelines. American Association of Physicists in Medicine 

(AAPM) report number 4, “Basic Quality Control in Diagnostic Radiology” (1978), was followed to 

ensure Entrance Skin Exposure Guide (ESEG) was achieved. A diagnostic medical x-ray survey 

checking ESEG for different projection limits was followed. The QA of the x-ray machine included 

checks on the kVp, half value layer (HVL) determination for beam quality, exposure timing accuracy, 

beam collimation and alignment testing, and film-screen contact testing. Table 3-4 through Table 3-6 

summarizes the parameters tested and the allowed tolerances as stated in the PORTS procedure 

(Bassett 1985). 

Table 3-4. Medical x-ray quality assurance parameters/PORTS. 

kVp requirements +/- 4 kVp (about 4%)

Timing requirements t +/- 5 % for t > 10 msec and t +/- 20 % for t < 10 msec 

+/- 10% is used at PORTS no matter what the time.

Beam alignment, light and radiation field congruence 

requirements

less than 2% of the source to image distance (SID) or 2 cm.
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The limits for HVL are as follows: 

Table 3-5. Half value layer limits . 

Measured kVp Minimum HVL (mm Al)

50 1.3

60 1.3

70 1.5

80 2.3

90 2.5

100 2.7

110 3.0

120 3.2

130 3.5

140 3.8

150 4.1

Source: Bassett 1985, “Medical x-ray Quality 

Assurance Tests,” p 4

The ESE limits are as follows:

Table 3-6. Entrance skin exposure limits. 

Projection ESEG (mR)

Chest (P/A) 30

Skull (Lat) 300

Abdomen (A/P) 750

Cervical Spine (A/P) 250

Thoracic Spine (A/P) 900

Full Spine (A/P) 300

Lumbo-Sacral Spine (A/P) 1,000

Retrograde Pyelogram (A/P) 900

Feet (D/P) 270

Source: Bassett 1985, “Medical x-ray Quality 

Assurance Tests,” p 6

From 1979 to 1994 a manual technique setting of 0.1 sec at 200 mA and 110 kVp was utilized for 

chest P/A views. (Communication with medical x-ray technologist.) After 1994 the exposures were 

photo-timed. To be more claimant favorable the manual techniques are utilized for Type I through 

Type III machines. 

X-ray organ dose estimates for occupational x-rays administered at PORTS are made for Type I 

equipment (used from 1970 through 1978), Type II equipment (used from 1979 to 1991), and Type III 

equipment (used from 1992 to the present). 

For the posterior/anterior view (P/A), a standard SID of 72 inches (183 cm) was used. Additional 

information indicated that all of the x-ray machines were single phase and that there was no air gap 

between the patient and the film. QA checks of the Type II and III machine indicated a 3.3 mm Al 

HVL. A value of 3.5 mm Al HVL would be claimant favorable for types II - III. Tables A-1 and A-2 list 

organ doses for P/A 14” x 17” chest films. 

For the LAT, 2.5 times the P/A entrance kerma value was used to estimate the LAT entrance kerma 

value. Tables A-3 and A-4 list organ doses for LAT 14” x 17” chest films. 
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3.3.5

For convenience and possible application to cases in which the standard PORTS protocol was not 

followed, or for generic use, the effect of various technical factors has been tabulated below in Table 

3-7.

Diagnostic X-Ray Technique Generalizations 1954 to Date

Air kerma was corrected for the thickness of the chest (26 cm) and for distance between the chest 

and the plane of the film (5 cm) to obtain the air kerma at skin entrance. The higher 3.5 mm Al 

filtration value was used since the dose conversion factors would be higher for 3.5 mm compared to 

lower values and thus more conservative and claimant favorable.

Table 3-7. Relationship of beam intensity and various technical factors.

Parameter Units Relationship with intensity

Applied voltage kVp Intensity proportional to 1.7 power of kVp

Tube current mA Linear

Exposure time s Linear

Filtration mm Al Intensity decreases by ~40% for each additional mm Al

Patient size

(chest thickness)

25-27 mm

>27 mm

Dose increased by factor of 1.5

Dose increased by factor of 2

Distance d Approximately inverse square relations (1/d2)

Uncertainty +30% Assume all errors are positive, + 30% should be used

Re-takes +5% Assume all workers had re-takes equal to 5% average

Source: ORAUT-TKBS-0006-3 TBD 2003, p6

3.3.5.1 Collimation

Collimation refers to the size of beam. Early, the philosophy was to use a fairly large aperture (i.e. 

limited collimation) to ensure that the entire area of interest was included in the radiograph. 

Subsequently, because of patient protection concerns, beams were collimated such that the smallest 

beam consistent with the area of interest was used, thereby limiting the area of the patient exposed, 

and, in the case of chest radiography, minimizing dose to organs such as gonads, thyroid, and 

gastrointestinal tract. Wochos et al. (1979) analyzed the 1972-1975 Nationwide Evaluation of X-Ray 

Trends (NEXT) data and found that at some facilities, primarily Internal Medicine and Medical GPs, 

the beam area to film area ratio could be as high as 2.0. 

In early years of operation (pre-1970), x-ray beam or scatter measurement data, techniques, or beam 

port information may not be available to estimate the collimation of the x-ray beam. Feldman et al. 

(1957) noted wide variation in their review of x-ray dose literature in 1957. Through measurements, 

Feldman et al. (1957) noted a factor of 10 increase in the gonadal dose when no external collimation 

was used. 

Due to the reported variation in the literature and measurement data on the effects of collimation, the 

claimant favorable assumption of no external collimation of the primary beam should be used when 

measurement data, technique, or other information to describe the collimation are not available for xrays taken prior to 1970. This is based on the following claimant favorable assumptions and 

professional judgment:

In the late 1950s, there was significant research into the gonadal dose and the reasons for the 

observed variation in dose. This research described the effects of filtration, collimation, and centering. 

By the early 1960s, techniques were being modified incorporating additional collimation. While these 

techniques were likely fully incorporated at most DOE facilities by 1965, to allow for the possibility that 
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some smaller facilities might not have had the resources to update their equipment and to be claimant 

favorable, the year 1970 was selected. 

In 1968, the National Council on Radiation Protection and Measurements (NCRP) in Report 33 

updated their guidance on medical x-ray protection. While many DOE facilities had probably already 

incorporated the guidance in this report, some smaller facilities might not have incorporated the 

guidance by 1968. To ensure that these facilities were in fact in conformance with the 1968 

recommendations, an additional two-year period was added. 

By the late 1950s, reports in the literature of most of the surveys of medical x-ray facilities revealed 

low gonadal doses, indicating adequate collimation. A few surveys clearly indicated the use of 

collimation was limited. Of the eight surveyed facilities at Oak Ridge, only one (13%) had a 

moderately high male gonadal dose (5 mrad). All of the other facilities, the male gonadal dose was 

less than 2 mrad. Variation between the other facilities appeared to be the result of differences in the 

use of filtration and cone size. Since most facilities were using some form of collimation by the late 

1950s, by the mid 1960s most, if not all, facilities were probably using some form of collimation. 

Since references as to when all facilities were using adequate collimation were not found, professional 

judgment was used to estimate this time-period to be the mid 1960s. To fully assure claimant 

favorability, this assumption has been further expanded by 5 years to 1970 to allow for the uncertainty 

in professional judgment. (ORAUT-OTIB-0006, section 2.4)

Review of the available documentation pertaining to the occupational medical program at PORTS 

from 1954 to the present revealed that only one diagnostic medical radiographic procedure was 

administered in connection with pre-employment or regular post-employment medical examinations, 

Posterior-anterior (P/A) 14” x 17” chest film. The LAT chest film was included in case records indicate 

their usage. Accordingly, only doses from these two techniques were evaluated. Any other 

radiographic examinations of PORTS employees that might have occurred were non-occupational in 

the sense that these were necessitated by illness or injury and hence not a part of the employee 

physical examination process. Thus, there is no indication in the records that other diagnostic 

radiographic examinations were administered as a part of the occupational medical program.

3.4 ORGAN DOSE CALCULATIONS

ICRP Publication 34 (1982) provides tables of average absorbed dose (mGy) in selected organs for 

selected x-ray projections at 1 Gy entrance kerma (i.e., air kerma without backscatter), for selected 

views (including P/A), and for selected beam qualities (i.e., various HVLs). These tables provide the 

basic dose conversion factors for converting air kerma to organ dose. The average air kerma rates 

for the different machines are calculated using the cGy per mAs provided in NCRP No. 102, Table B.3 

(1989) for specific voltage, current, phase of the machine, and distance to the film. 

Finally, the PORTS organ doses are found by multiplying the ICRP 34 organ dose conversion factors 

by the entrance air kerma values. The resulting PORTS x-ray organ doses for all machines are in 

Tables B.01 through B.04. The doses are shown in units of dose equivalent or rem, assuming a 

quality factor of 1.0 for x-rays. PORTS records will indicate the view and in most cases only one view 

was taken per medical examination. 

3.4.1

Default values of entrance skin exposure have been developed for the three most commonly used 

occupational medical diagnostic x-ray procedures: P/A chest radiography; lateral chest radiography; 

Photofluorography (1954-1957)
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date: 07/07/2006 Page 14 of 25

photofluorographic chest films when actual measurement data or knowledge of technique factors are 

absent and minimal collimation is assumed. The default values are considered to be maxima 

developed from review of patient doses as reported in the literature, machine characteristics, and 

knowledge of x-ray procedures used during the time periods indicated. Sufficient conservatism was 

included in the determination of the default values to ensure with near certainty that the actual 

exposures from the specified procedures would not exceed the default values, thus ensuring claimant 

favorability. In determining these factors, it was assumed that a minimum of filtration was used along 

with low kilovoltage techniques, slow film speeds with standard development, and no additional 

collimation or use of cones. The default entrance kerma values for the three procedures are given in 

Table 3-8. The PFG period of applicability is based upon the discovery of one PFG performed as 

appeared in one claimant’s file in October of 1957. (ORAUT-OTIB-0006 2005)

Table 3-8. Default dose values by procedure. 

Period

Entrance kerma, cGy Entrance kerma, cGy Entrance kerma, cGy

P/A chest Lateral chest Photofluorographic chest

Pre-1970 0.20 0.50 3.0

The above default values can then be used as described above in lieu of actual measurement data or 

entrance kerma (ESE) derived from technique factors. These default ESE values were used in 

conjunction with uncollimated dose conversion factors as listed in the complex-wide x-ray TBD 

guidance document in Table 4.0-1 in ORAUT-OTIB-0006.

Organ doses for chest photofluorography are calculated in an analogous manner to organ doses 

calculated for conventional radiography using the ESE values. Table 4.0-1 provides dose conversion 

factors for the ICRP organs based on a distance of 152 cm and beam quality of 2.5 mm Al HVL. 

3.4.2

Prior to about 1970, x-ray measurement data, techniques, or beam port information may not be 

available to estimate the collimation of the x-ray beam. Several papers in the literature have 

considered the effects of cone size and centering on the organ dose, and concluded that filtration, 

kVp, and the smallest possible cone size were most important to reduce these doses (Feldman et al. 

1958). Due to the reported variation in the literature and measurement data on the effects of 

collimation, it is claimant favorable to assume minimal or no additional external collimation was used 

when measurement data, technique, or other information to describe the collimation are not available 

for x-ray procedures performed prior to 1970. 

Pre-1970 (1958-1969)

Without collimation, organs normally outside of the primary beam are exposed to the primary beam. 

This necessitates the use of dose conversion factors from ICRP 34 other than those for a P/A or lat 

chest x-ray, since ICRP 34 dose conversion factors are based on properly collimated beams. For 

uncollimated beams used prior to 1970, the uncollimated dose conversion factors as listed in the 

complex-wide x-ray TBD guidance document in Table 4.0-1 were used. The entrance kerma values 

for pre-1970 x-ray machine that are used in the organ dose calculations are listed in Table 3-8. The 

calculation is analogous to the organ doses calculated for conventional radiography as illustrated in 

section 3.3.4.

3.4.3

Default values as presented in Table 3-9 were obtained from the site wide x-ray medical dose 

technical basis document. The default values were determined from a review of patient doses as 

reported in the literature, machine characteristics, and knowledge of x-ray procedures used during the 

Type I Machine (1970-1978)
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date: 07/07/2006 Page 15 of 25

time period indicated. In determining these factors it was assumed that a minimum of filtration was 

used along with low kilovoltage techniques, slow film speeds with standard development, and no 

additional collimation or use of cones (ORAUT-OTIB 2005). An HVL of 2.5 mm was used in the organ 

dose calculations.

Table 3-9. Default dose values by procedure. 

Period

Entrance kerma, cGy Entrance kerma, cGy

P/A chest Lateral chest

1970-1978 0.20 0.50

3.4.4

Based on the techniques in Table 3-3, the mAs for the types of equipment were calculated for each 

view:

Type II Machine (1979-1991)

Current (mA) × Exposure Time (sec) = Current for View (mAs) 

Example for Type II P/A view: 200 mA × 1/10 s = 20 mAs

(3–1)

The air kerma rate for 110 kVp was determined to be 0.25 cGy per 100 mAs (see Table B.3 of 

NCRP 102) and the air kerma was calculated after converting the rate to air kerma per mA.

Current for View (mAs) × Corrected Air Kerma Rate (cGy/mAs) = Air Kerma (cGy)

Example for Type II P/A view: 20 mAs × 0.0025 cGy/mAs = 0.05 cGy

(3–2)

Multiply by 0.6 to account for 3.5 mm Al versus 2.5 mm Al Table B.3 NCRP 102 

is based upon; 

{see Table 3-7} 0.6 × .05 cGy = .030 cGy

(3–3)

The air kerma was corrected for the thickness of the chest (26 cm) and for distance between 

the chest and the plane of the film (5 cm) to obtain the air kerma at skin entrance.

Air kerma at 183 cm x SID squared ÷ SSD squared = air kerma at skin entrance

Example for Type II P/A view: 0.03 cGy × (183 cm)2 ÷ (152 cm)2 = 0.043 cGy

(3–4)

Air kerma at skin entrance was multiplied by the dose conversion factors in Table A.2 through 

A.8 of ICRP Publication 34 for P/A chest and HVL of 3.5 mm Al eq.

Air Kerma (cGy ) × Dose conversion factor = Dose for View (cGy) (3–5)

Example for Type II P/A view, dose to thyroid: 

0.043 cGy × 62 mGy/Gy × 1 Gy/100cGy × 1 rad/10 mGy = 2.67 E-3 rad

3.4.5

The survey measurements made by the FDA in 1992 which yielded 0.64 mR/mAs will be utilized to 

estimate the ESE. As indicated in Table 3-7 a linear adjustment for mA is needed. The technique 

factor for time used was 0.1 seconds and probably less because of the photo-timing system. The 

technique factor for kVp was 110 and for the current technique factor was 200 mA, the same 

parameters used for the FDA measurements. Therefore, no adjustments are needed for these 

technique factors. All other parameters were the same. The ESE calculation adjustment based on 

the 1992 FDA measurements is as follows:

Type III Machine (1992-Present)
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date: 07/07/2006 Page 16 of 25

0.64 mR/mAs × 0.1 sec × 200 mA = 12.80 mR

The FDA survey was used instead of the PORTS survey conducted in 1994 because the FDA 

measurement included the use of a phantom and is likely more reliable.

Based on the techniques in Table 3-3, the mAs for the types of equipment were calculated for each 

view in the same manner as presented in section 3.3.4 above. Table 3-10 lists the reference organ 

used to approximate the organ analogue doses.

Table 3-10. Analogues for IREP organs not included in ICRP 34. 

Anatomical location ICRP 34 reference organ IREP organ analogues

Thorax Lung Thymus

Esophagus

Stomach

Bone surface

Liver/gall

bladder/spleen

Remainder organs

Abdomen Ovaries Urinary/bladder

Colon/rectum

Head and neck Thyroid Eye/brain

3.5 UNCERTAINTY

Error, defined as deviation from the correct, true or conventionally accepted value of a quantity, and 

uncertainty, defined in terms of the potential range of a stated, measured, assumed or otherwise 

determined value of a quantity, provides an indication of the confidence of the dose estimates. Error 

implies knowledge of what the correct or actual value is, which is, of course, not known. Hence a 

more appropriate term is uncertainty, which is expressed in terms of a confidence level, e.g. 99% (i.e. 

that the correct or true value, although not actually known, has a 99% probability of falling within the 

range cited) and includes both precision or reproducibility of the measurement and accuracy, or how 

close the measurement or estimate of dose comes to the actual or correct value (ORAUT-TKBS-0003

2003, p5). 

Although in theory a large number of factors can introduce uncertainties or affect the x-ray machine 

output intensity and dose to the patient, in practice only four factors can be reasonably considered to 

have an impact on dose uncertainty. These are 1) variation in applied kilovoltage, 2) variation in 

beam current, 3) variation in exposure time, and 4) distance from the patient to the source of the X 

rays (SSD). The influence of such other factors as use of screens, grids, reciprocity failure, film speed 

and development, while potentially variable, would not affect the beam output intensity (ORAUTTKBS-0003 2003, p5).

For a given set of machine settings and parameters, x-ray output should theoretically be constant and 

unvarying. However, this is not true in practice; although output is essentially constant unless focal 

spot loading occurs such as might be the case when the power rating of the machine is exceeded. It 

is unlikely that power ratings were ever exceeded since so doing would be difficult to achieve in 

practice and would result in damage to the x-ray tube. However, even with the use of so-called 

constant voltage transformers to control line voltages, slight variations may occur in line voltage input 

or other internal voltages, which in turn could alter the kVp of the output beam. In general, for a given 

kVp setting, variation in kVp falls within ± 5% of the machine setting (Siebert et al. 1991). Since as 

noted above beam intensity is approximately proportional to the 1.7 power of the kilovoltage, this 

translates to an uncertainty of approximately ± 8.7%with respect to output beam intensity in the 80 to 
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date: 07/07/2006 Page 17 of 25

110 kVp range used for diagnostic radiographs at the PORTS Site . For conservatism, this is rounded 

up to ± 9% (ORAUT-TKBS-0003 2003, p 5 and ORAUT-TKBS-0006-3 2003, p 14).

Similarly slight variations in tube current are normal; as a tube ages, or heats up from usage, tube 

current may change and typically will drop. Hence, all other factors remaining constant, beam 

intensity will be reduced, and in direct proportion to the change in tube current. Typically, the 

reduction in beam output from current variation is not more than a few per cent under normal 

operating conditions; large decreases in beam output will be readily detected and result in 

maintenance on the machine to restore the output or, as a temporary stopgap measure, increase in 

the current or kVp to provide the necessary intensity for proper radiography. There is no evidence to 

suggest that these stopgap measures were ever necessary or applied at the PORTS Site. For a 

given kVp setting, output of the beam is a function of the tube current, which in turn is measured by a 

milli-ammeter on the machine and measures average tube current. The measurement is subject to 

uncertainties, and in addition there may be minor changes in output as the tube heats up from normal 

usage. These variations are typically small, and hence uncertainty in beam output attributable to 

current variation has been estimated at ± 5% (ORAUT-TKBS-0003 2003, p 6).

Another parameter that has potential to affect the dose, perhaps significantly, from a diagnostic 

radiograph relates to the time of exposure. This can be readily understood by noting that a full wave 

rectified machine produces 120 pulses per second of x-rays. For an exposure time of 1/20 of a 

second, only six pulses would result. A small error in the timer that resulted in a change of only ± 1 

pulse would correspondingly affect the output by ± 17%; for an exposure time of 1/30 of a second, the 

change in output corresponding to a deviation of ±1 pulse is ± 25%. Early mechanical timers were 

notoriously inaccurate, although timer accuracy improved significantly with the introduction of 

electronic timers. PORTS timer was held to a +/- 10 % criteria from about 1979. However, once 

again for conservatism, uncertainty in beam output attributable to timers will be assumed to have an 

upper limit of + 25% (ORAUT-TKBS-0003 2003, p 6).

The final factor that is likely to affect patient dose relates to distance from the source of the x-rays, 

which is a determinant of the entrance skin exposure. For a given individual, the SSD will be 

determined largely by the thickness of the patient, and how accurate the positioning is. For a typical 

patient, this variation in SSD is estimated at no more than a few centimeters, with an upper limit of 

perhaps 7.5 cm. Using Inverse Square, this indicates an uncertainty of ± 10% from this source 

(ORAUT-TKBS-0003 2003, p 6).

There are two approaches to determination of the combined uncertainty from the above four potential 

sources of uncertainty. The first, and most conservative in that it gives the greatest range, would be 

to assume that the uncertainties are additive, which would give an uncertainty range of up to 9 + 5 + 

25 + 10 = 49. However, a more reasonable approach would be to assume that the uncertainties are 

in fact random, and to compute the statistical root mean square (RMS) value. The RMS value is 

simply the square root of the sum of the squares, and computes as ± 28.8%. Thus, for any individual 

entrance skin exposure (ESE) or derived organ dose, an uncertainty of ± 30 % l may be assumed; for 

further conservatism it may be appropriate to assume that errors are all positive, and only the + 30 % 

should be used (ORAUT-TKBS-0003 2003, p 6).

3.6 DOSE RECONSTRUCTOR INSTRUCTIONS

The information below provides instructions for dose reconstructors in determining organ doses from 

occupational medical (x-ray) procedures. For the purpose of evaluating probability of causation, x-ray 

doses are always considered acute, and are photons with energy E=30-250 keV.
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date: 07/07/2006 Page 18 of 25

3.6.1

Maximizing Medical X-ray Dose

Assignment of Organ Doses from X-ray Procedures: Approach for Dose 

Reconstructions

The organ doses assigned for each x-ray procedure are the highest doses to any organ in the 

relevant group as listed in Tables B1-B4 should be multiplied by a factor of 1.3 to account for 

uncertainty. The result will be the maximizing of annual x-ray doses that may be applied in dose 

reconstructions for likely non-compensable cases. At least one x-ray per year or partial year of 

employment should be assumed taken in order to be claimant favorable.
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date: 07/07/2006 Page 19 of 25

REFERENCES

American Association of Physicists in Medicine (AAPM), 1978, Report Number 4, “Basic Quality 

Control in Diagnostic Radiology.” 

Bassett, A. C., 1985, “Medical x-ray Quality Assurance Tests,” GAT S 39, (1 – 41), January 15. 

Braestrup, C. B., 1958, “Radiation Protection,” Charles C. Thomas, Springfield. 

Cardarelli, J., H. Spitz, C. Rice, R. Buncher, H. Elson and P. Succop, 2002, “Significance of Radiation 

Exposure From Work-Related Chest X-Rays for Epidemiological Studies of Radiation 

Workers, Amer. J. Indust. Med., 42:490-501.

FDA Bureau of Radiological Health, 1992, Inspection dated August 24, 1992. 

Feldman, A., Babcock, G. C. Lanier, R. R., and Morkovin, D., 1958, “Gonadal Exposure Dose from 

Diagnostic X-ray Procedures,” Radiology 71:197-207. 

International Commission on Radiological Protection, “Protection of the Patient in Diagnostic 

Radiology,” ICRP Publication 34, Annals of the ICRP, 9(2/3):1-82.

International Commission on Radiation Units and Measurements (ICRU), 1998, “Fundamental 

Quantities and Units for Ionizing Radiation,” ICRU Report 60, ”Bethesda: International 

Commission on Radiation Units and Measurements.” 

Laughlin, J. S., M. L. Muerk, I Pullman and R. S. Sherman, 1957, “Bone, Skin and Gonadal Doses in 

Routine Diagnostic Procedures,” American Journal of Roentgenology, Radium Therapy and 

Nuclear Medicine, 78:197-983. 

Morgan, R. H. and K. E. Corrigan, Eds., 1955, Handbook of Radiology, Chicago: The Year Book 

Publishers, Inc. 

National Institute for Occupational Safety and Health NIOSH, 2002, “External Dose Reconstruction 

Implementation Guideline,” OCAS-IG-001, rev 1, August. 

National Council on Radiation Protection and Measurements (NCRP), 1968, “Medical X-Ray and 

Gamma-Ray Protection for Energies Up To 10 MeV,”NCRP Report No. 33, Washington: 

National Council on Radiation Protection and Measurements. 

National Council on Radiation Protection and Measurements (NCRP), 1985, “SI Units in Radiation 

Protection and Measurement,” NCRP Report No. 82, Bethesda: National Council on Radiation 

Protection and Measurements.

National Council on Radiation Protection and Measurements (NCRP), 1989, “Medical x-ray, Electron 

Beam and Gamma-Ray Protection for Energies Up To 50 MeV,” NCRP Report 102, Bethesda. 

ORAUT-OTIB-0006 rev 03 PC-1, “Dose Reconstruction from Occupationally Related Diagnostic x-ray 

Procedures,” Ronald L. Kathern, Vernon E. Shockley, Elyse M. Thomas and Timothy D. 

Taulbee, 12/21/2005. 

ORAUT-TKBS-0003, “Technical Basis Document for the Savannah River Site to be used for 

EEOICPA Dose Reconstructions,” 8/21/2003. 
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date: 07/07/2006 Page 20 of 25

ORAUT-TKBS-0006-3, “Technical Basis Document for the Hanford Site – Occupational Medical 

Dose,” 9/16/2003. 

Portsmouth Health Physics Department, 1994 “X-ray QA survey,” March 3. 

Sante, L. R., 1946, Manual of Roentgenographic Technique, Ann Arbor: Edwards Brothers, p. 61. 

Seibert, J. A., G. T. Barnes and R. G. Gould, 1991, “Specification, Acceptance testing, and Quality 

Control of Diagnostic x-ray Imaging Equipment,” Medical Physics Monography, No. 20. New 

York: American Institute of Physics.

Trout, E. D., Jacobson, G., Moore, R. T., and Shoub, E. P., 1973, “Analysis of the Rejection Rate of 

Chest Radiographs Obtained During the Coal Mine ’Black Lung‘ Program,” Radiology 109:25-

27. 

Wochos, J. F., Detorie, N. A., and Cameron, J. R., 1979, “Patient Exposure from Diagnostic X-rays: 

An Analysis of 1972-1975 NEXT Data,” Health Physics 36:127-134.
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date: 07/07/2006 Page 21 of 25

ATTACHMENT A

OCCUPATIONAL MEDICAL DOSE

Page 1 of 5

A.0

PORTS conducted pre-employment and annual physical examinations as part of their occupational 

health program. These examinations typically included a P/A chest x-ray. For some workers, and 

occupations, chest x-rays could be more frequent. 

PORTS MEDICAL X-RAY

A.1

X-ray organ dose equivalents for occupational x-rays at PORTS are estimated for all years from 1954 

to present. The schedule for these exams for all PORTS employees over this time period is shown in 

Table A-1 through A-2, along with the organ dose information. Tables A-3 and A-4 are for P/A views 

for listed and unlisted organs in ICRP 34. X-ray organ dose estimates were made for 

photofluorography (1954-1960), per-1970 (1961-1969), Type I equipment (used from 1970 to 1978), 

Type II equipment (used from 1979 to 1991) and Type III equipment (used from 1992 to present). 

ORGAN DOSES FROM MEDICAL X-RAYS
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date:

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ATTACHMENT A

OCCUPATIONAL MEDICAL DOSE

Page 2 of 5

Table A-1. Dose equivalents for organs identified in ICRP 34 (1982) for P/A views.

Period Frequency

PORTS 

employee

Organ dose equivalents per 14” x 17” P/A chest (rem)

Air kerma at 

skin 

entrancea Thyroidd Ovariesd Testesd Lungsd Breastd Uterusd(embryo)

Bone 

marrowd

1954-1957

(PFG)b Annual All 3.000 0.52 0.025 0.005 1.350 0.147 0.025 0.276

1958-1969

(Pre-1970)c Annual All 0.200minimal

collimation

0.0348 0.025 0.005 0.0902 0.0098 0.025 0.0184

1970-1978

(Type I)

Annual All 0.100

2.5 mm HVL

0.0032 0.0001 0.000001 0.0451 0.0049 0.00013 0.0092

1979-1991 

(Type II)

Annual All 0.043

3.5 mm HVL

0.00267 0.000138 0.00000043 0.0262 0.00391 0.000129 0.00628

1992-present

(Type III)

Offered 

every 10 

years

Employees up 

to 30 years old.

0.0128

3.5 mm HVL 0.000794 0.000041 0.000000128 0.00781 0.00116 0.0000384 0.00187

Offered 

every 5 

years

Employees up 

to 45 years old.

Offered 

every 3 

years

Employees 

greater than 45 

years old.

Annually Asbestos

/Beryllium 

workers.

a. Air kerma at entrance skin in rem.

b. Photofluorographic chest entrance uncollimated kerma (2.5 mm Al HVL) ORAUT-OTIB-0006, Table 4.0-1.

c. Pre-1970 chest 99% confidence entrance uncollimated kerma (2.5 mm Al HVL) ORAUT-OTIB-0006, Table 4.0-1.

d. Organs identified in ICRP 34 (1982) for dose determination from air kerma skin entrance dose equivalent associated with chest radiography.
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date:

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ATTACHMENT A

OCCUPATIONAL MEDICAL DOSE

Page 3 of 5

Table A-2. Dose equivalent for IREP organs not included in ICRP 34 (1982) for P/A views.

Period Frequency

PORTS 

employee

Organ dose equivalents per P/A chest (rem)

Air kerma Thymus Esophagus Stomach

Bone 

surface

Liver/gall 

bladder/spleen

Urinary/ 

bladder

Colon/ 

rectum Eye/brain Skinc Remainder

1954-1957

(PFG)a

Annual All 3.000 1.35 1.35 1.35 1.35 1.35 0.025 0.025 0.096 4.05 1.35

1958-

1969(Pre1970)b

Annual All 0.200

minimal 

collimation

0.0902 0.0902 0.0902 0.0902 0.0902 0.025 0.025 0.0064 0.270 0.0902

1970-

1978(Type 

I)

Annual All 0.100

2.5 mm HVL

0.0451 0.0451 0.0451 0.0451 0.0451 0.0001 0.0001 0.0032 0.135 0.0451

1979-1991 

(Type II)

Annual All 0.043

3.5 mm HVL

0.0262 0.0262 0.0262 0.0262 0.0262 0.000138 0.000138 0.00267 0.0602 0.0262

1992-

present

(Type III)

Offered 

every 10 

years

Employees 

up to 30 

years old.

0.0128

3.5 mm HVL 0.00781 0.00781 0.00781 0.00781 0.00781 0.0000451 0.0000451 0.000794 0.0179 0.00781

Offered 

every 5 

years

Employees 

up to 45 

years old.

Offered 

every 3 

years

Employees 

greater than 

45 years old.

Annually Asbestos/

beryllium 

workers.

a. Photofluorographic chest entrance uncollimated kerma (2.5 mm Al HVL) ORAUT-OTIB-0006, Table 4.0-1

b. Pre-1970 chest 99% confidence entrance uncollimated kerma (2.5 mm Al HVL) ORAUT-OTIB-0006, Table 4.0-1

c. Entrance skin dose is entrance skin exposure calculated from air kerma, multiplied by a backscatter factor of 1.4 from NCRP 102, Table B-8.
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date:

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ATTACHMENT A

OCCUPATIONAL MEDICAL DOSE

Page 4 of 5

Table A-3. Dose equivalents for organs identified in ICRP 34 (1982) beam quality for LAT views.

Period Frequency

PORTS 

employee

Organ dose equivalents per LAT chest (rem)

Air kerma at skin 

entrancea Thyroidc Ovariesc Testesc Lungsc Breastc Uterusc(embryo)

Bone 

marrowc

1958-1969

(Pre-1970)a Annual All 0.500uncollimated

0.0685 0.013 0.0025 0.1100 0.128 0.013 0.0185

1970-1978

(Type I)

Annual All 0.250

2.5 mm HVL

0.0288 0.00015 0.000025 0.055 0.0638 0.00015 0.00925

1979-1991 

(Type II)

Annual All 0.108

3.5 mm HVL

0.0162 0.000172 0.0000108 0.0333 0.034 0.000151 0.00656

1992-

present

(Type III)

Offered 

every 10 

years

Employees up 

to 30 years old.

0.032

3.5 mm HVL 0.00483 0.0000512 0.0000032 0.00992 0.0101 0.0000448 0.00195

Offered 

every 5 

years

Employees up 

to 45 years old.

Offered 

every 3 

years

Employees 

greater than 45 

years old.

Annually

Asbestos/

beryllium 

workers.

a. Air kerma at entrance skin in rem.

b. Pre-1970 chest entrance uncollimated kerma (2.5 mm Al HVL) ORAUT-OTIB-0006, Table 4.0-1.

c. Organs identified in ICRP 34 (1982) for dose determination from air kerma skin entrance dose equivalent associated with chest radiography.
Document No. ORAUT-TKBS-0015-3 Revision No. 02 Effective Date:

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ATTACHMENT A

OCCUPATIONAL MEDICAL DOSE

Page 5 of 5

Table A-4. Dose equivalent for IREP organs not included in ICRP 34 (1982) for LAT views.

Period Frequency

PORTS 

employee

Organ dose equivalents per LAT chest (rem)

Air kerma Thymus Esophagus Stomach

Bone 

surface

Liver/gall 

bladder/

spleen

Urinary/ 

bladder

Colon/ 

rectum

Eye/

brain Skin b Remainder

1958-1969

(Pre-1970)a Annual All

0.500

uncollimated0.110 0.110 0.110 0.110 0.110 0.013 0.013 0.0685 0.675 0.110

1970-1978

(Type I) Annual All 0.2502.5 mm HVL 0.055 0.055 0.055 0.055 0.055 0.00015 0.00015 0.0288 0.338 0.055

1979-1991 

(Type II) Annual All 0.1083.5 mm HVL 0.0333 0.0333 0.0333 0.0333 0.0333 0.000172 0.000172 0.0162 0.151 0.033

1992-present

(Type III)

Offered every 

10 years

Employees 

up to 30 

years old.

0.032

3.5 mm HVL 0.00992 0.00992 0.00992 0.00992 0.00992 0.0000512 0.0000512 0.00483 0.0479 0.00992

Offered every 

5 years

Employees 

up to 45 

years old.

Offered every 

3 years

Employees 

greater than 

45 years old.

Annually

Asbestos/

beryllium 

workers.

a. Pre-1970 chest entrance uncollimated kerma (2.5 mm Al HVL) ORAUT-OTIB-0006, Table 4.0-1

b. Entrance skin dose is entrance skin exposure calculated from air kerma, multiplied by a backscatter factor of 1.4 from NCRP 102, Table A-8